This invention is concerned with the magnetic properties of superconducting materials. The field of superconductivity was revolutionized in April 1986 with the discovery by Bednorz and Muller that certain types of metallic oxides become superconducting at temperature considerably higher than the highest critical temperature (T.sub.c) previously known for any superconducting material. Superconductors exhibit zero resistance, diamagnetism (the Meissner effect), Josephson tunneling, and a forbidden energy gap. These effects are observed in both soft (type I) and hard (type II) superconducting materials. The above phenomena have been extensively studied to understand the origins and physical mechanisms of these attributes and to find uses for these materials to meet the needs of society.